REPORT: From Barcelona to Brackley, and Back
The team focused on race si...

The team focused on race simulations and gathering data on Pirelli's 2018 tyres during the penultimate day of pre-season testing.

Thursday's running at the Circuit de Barcelona-Catalunya was the most productive of testing so far for the Mercedes-AMG F1 W09 EQ Power+.

The new car was properly put through its paces with a series of race runs and tyre tests, with the drivers getting their heads down and concluding the day with a total lap count of 181.

So far, the W09 has completed 839 laps of pre-season testing, which is 3,906km - the equivalent of driving from Barcelona to Brackley, and back again, with a few hundred kilometres still to spare.

While Lewis Hamilton and Valtteri Bottas failed to feature at the top of the timesheets, the team's sole focus was on high-fuel, race runs - mainly using the Medium tyre compound.

We continued with the trend of splitting running between drivers, with Valtteri first to drive and Lewis taking over in the afternoon. Both will complete their final laps of pre-season testing on Friday.

'It will be very different in Australia'

Valtteri kick-started the day with a series of longer runs, quietly racking up the laps across the morning session and departing for the lunch break with 97 laps under his belt.

The Finn was ninth quickest on Thursday, with his best lap of 1:19.532 set on the Medium tyre towards the end of the morning session.

"Today was one of those days that you learn the most from as a driver," Valtteri said. "For the first time this year, I did a race simulation with a proper race distance. You have the mind-set that it's a race and try to take everything out of the car and the tyres.

"A real race distance gives you more time to learn and experience different driving lines. The race run seemed quite competitive, everything felt alright. The Medium tyre is behaving well on this track and in these conditions.

"Both the team and I have been understanding the new tyres more and more every day. But, we need keep in mind that it will be very different in Australia.

"I still have another half day left in the car tomorrow afternoon. It will be the last time I'm going to be in the car before Melbourne, so we need to make sure we make the most out of that time, run all the tests we still need to do and learn as much as we can. Overall, today was a very positive day and a real teaser for Melbourne."

'I'm really proud of everyone'

Lewis returned to the cockpit of the W09 in the afternoon, quickly getting to work on race simulation work and data gathering on Pirelli's new tyre compounds.

The four-time World Champion leap-frogged team-mate Valtteri with a 1:19.296 in the final 30 minutes of the session, also setting his best time on the Mediums.

"Our week has been very productive so far," Lewis explained. "We got through everything we needed, reliability has been fantastic and the car feels great.

"We have not been working on balance, but in terms of some of the issues we had last year, a lot of them appear to have been removed. We get great correlation when we change bits of the car, so it's been a smooth transition this year so far.

"The track is very different to what it used to be because they resurfaced it. So it's difficult to know what all the experience means once we get to Melbourne. But, I definitely feel that we're moving in a positive direction. I'm really proud of everyone. They've been working so well in the team, the synergy is great at the moment.

"On another note, I know it's International Women's Day today so happy International Women's Day to all the ladies, to my Mum also and to my sisters. I think it's an amazing time for women. In my team, there's more women engineers than ever before. So I think it's a good time and I hope everyone has an amazing day."